package com.tzm.demo;

public class Test2 {
  public static void main(String[] args) {
    Integer a = 2;
    Integer b = 3;
    swap(a, b);
    System.out.println(a + ", " + b);
  }
  public static void swap(Integer a, Integer b) {
    Integer tmp = a;
    a = b;
    b = tmp;
  }

}

